The present invention relates to a unit circuit accommodated in a switchboard of a control center or the like, and a wiring board device used for forming the unit circuit, and a method for forming the unit circuit.
FIG. 12 shows a conventional unit circuit accommodated in a switchboard of a control center or the like. It comprises a unit case or housing 1, in which a molded-cased circuit breaker 2, a current transformer 3, a zero-phase current transformer 4, an electromagnetic switch 5, an overcurrent relay 6, auxiliary relays 7 and 8, and a terminal block 9 are disposed. These functional components are connected to each other by control circuit wires 14 and to main circuit wires 13, as illustrated in FIG. 13. The layout of the components is determined taking account of the spaces for the work of wiring.
Because the conventional unit circuit is configured as described above, the wiring between the components and the terminals has to be made for each different design or type of circuit. As a result, the work of wiring is time-consuming. Moreover, considerable space is required for the work of wiring around each component or between the adjacent components. This places a limitation on size reduction of the unit circuit.